In the dispensing of fluid from large volume containers such as five gallon pails achieving a smooth rapid flow without surging or gluging is always desirable. Such nonpulsating flow is currently accomplished by a variety of arrangements all of which are successful to a degree and al of which have certain deficiencies which the invention seeks to overcome. Incorporating an anti-glug feature in the primary pouring spout dispensing closure is perhaps the most popular approach in that it avoids any addition of labor in the pail manufacture. Such vented dispensing closures, however, are frequently more costly to produce but more importantly, their construction which attempts to freely permit the entry of air at atmospheric pressure, significantly restricts the outflow of fluid. The resulting dispensing performance of these arrangements where air is trying to enter and fluid is trying to exit through the same opening can only be characterized as "disappointing". Another common and very effective arrangement is to provide a completely separate vent closure inserted in the container top diametrically opposite the dispensing closure. This construction produces an excellent flow characteristic but is quite costly in pail manufacturing terms due to the additional component and labor for its insertion. The most cost effective approach, of course, is to simply punch a hole in the top of the container opposite the dispensing closure. This method lacks practicality in that it tends to freely let fluid out and foreign matter in. Finally, several arrangements have been brought forward attempting to integrate an anti-glug vent into the structure of the pail top which have obvious security advantages but have fallen short of commercial use due to undue complexity of molding or impracticality of function.